I read both. Lincoln repeated the exacts same words at both debates. He did it in the 6th to answer Doglas' charge that he said one thing in front of an audience in Southern IL. and another in Northern IL.
His position was consistent throughout. No, he didn't think blacks were socially or intellectually equal to whites, but he still thought slavery wrong and that blacks were entitled to 'life, liberty, and the pursuit of happiness (i.e. property)' just as much as whites.
You are the one who posted his quote out of context -- just as Lost Causers and Leftist revisionists have been doing for decades. They both distort his words and historical record to serve their own ends. Neither has any interest in the truth.